The present invention relates to Colored Nanolithography on glass and plastic substrates. Particularly, the present invention relates to a simple, versatile and inexpensive method of generating submicron-scale color pattern on various surfaces such as overhead projector paper (OHP) and glass. More particularly, the present invention relates to method for generating colored parallel lines with submicron scale spacing between each other and microarrays of ink spots positioned at predetermined angles and spacing. The method of the present invention has enormous application potential in information storage, in storing hidden information in currency notes, in sensors, and in so called xe2x80x9cE-paperxe2x80x9d for displays. The use of flexible plastic material like OHP paper enhances the possibility of storing designs in foldable substrates.
Generating fast, easy, inexpensive, high resolution two and three dimensional patterned structures on solid surfaces has been a challenge leading to the discovery of a number of methods for imprinting patterns in addition to photolithography. Important among them are soft lithography and micropen lithography. In soft lithography, different micromolding techniques are used to generate structures at multiple length scales and dimensions using a variety of substrates and imprint materials. Molecular self-assembly has helped improve the resolution of structures further. All these methods are guided by applications such as microreactors, sensors, microelectromechanical systems, electronic devices at micro and nano scales.
Reference can be made to Xia, Y Whitesides, G. M. Angew, Chem. Int. Ed. 1998,37,550 wherein soft lithographic methods were discussed. Reference of micropen lithography can be found in Fan, H.; Lu, Y.; Stump, A.; Reed, S. T.; Baer, T.; Schunk, R.; Perez-Luna, V.; Lopez, G. P., Brinker, C. J. Nature 2000, 405, 56. However, none of the above methods has emphasized the generation of colored pattern that has enormous application potential in information storage, sensors, the so-called xe2x80x9cE-paperxe2x80x9d for displays. Storage of information in xe2x80x9ctruexe2x80x9d colors is expected to shorten the processing time for retrieval of information considerably. Also, imprinting of patterns on flexible plastic materials might enhance the versatility towards material application. Although, ink-jet printing has been used to obtain organic light emitting devices of doped polymers, there have been no reports of generating patterns on color at the submicron scale.
The drawback of the present method of nanolithography by using a stamp is that it employs only non-colored stamping of materials on different substrates. Thus there is no example of colored nanolithography in the form of stamping otherwise known as soft lithography in the literature. The fundamental drawback of the present method is that there is no scope of storing colored information (image) in this method. Thus storage and retrieval of colored information (picture etc.) is either not possible or not specified at all. Indeed there is a need for new methods of generation of colored nanolithography that will be useful for storing colored information, sensors, catalysts etc, In addition, there is no example of stamping with nanometer resolution on plastic substrates. This is important as one could store information in the form of electronic materials made of plastic substrates. There is a need to have colored nanolithographic patterns on plastic substrates and glass.
The main object of the present invention is to provide Colored Nanolithography on glass and plastic substrate, which obviates the drawbacks as, detailed above.
The present invention provides for the first time a method for nanolithography in colour using the principle of soft lithography. As demonstration of the present method, the Inventors have used permanent marker pen ink of various colors as the xe2x80x9cinkxe2x80x9d and components of commercially available compact disk as the mold (stamp) to store information.